From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Fri, 5 Apr 2002 10:28:54 -0700 From: Matt Porter To: Greg Griffes Cc: linuxppc-embedded@lists.linuxppc.org Subject: Re: 7400 mmu_init problem Message-ID: <20020405102854.A15453@home.com> References: <00e101c1dc8e$f4f8d720$6401a8c0@attbi.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <00e101c1dc8e$f4f8d720$6401a8c0@attbi.com>; from ggg@ieee.org on Fri, Apr 05, 2002 at 05:45:08AM -0500 Sender: owner-linuxppc-embedded@lists.linuxppc.org List-Id: On Fri, Apr 05, 2002 at 05:45:08AM -0500, Greg Griffes wrote: > > Hello, > > I am trying to port linuxppc_2_4_devel to a custom 750 design. > Using the GNU binutils and gcc-core-2.95.3 tools. 7400 (subject line) or 750? :) It doesn't matter though. > After ppc_md.progress reports "MMU: exit" in mm/init.c::mmu_init() > the kernel goes into panic() and dies there. > > I have been using a lousy, unreliable JTAG debugger. Today, I have a > BDI2000 and will be learning how to use it and GDB :-)) Even with a bad debugger you should be able to dump log_buf to see the oops message. > Has anyone experienced this in the past? If I had a nickel for every time... > Does anyone have a rough idea of the cause of the problem? > My guess is that it could be many possible problems, but, it has to > be something that I did wrong in _setup.c I haven't changed > much in the kernel itself. We can only guess since we don't know your hardware and can't see your board specific code. However, you made it out of MMU_init and most likely got to start_kernel:setup_arch. I can only guess that you access an unmapped area in your _setup_arch. > The low level IO is mapped at 0xEC00_0000; could that be a problem? What low level IO? Are you attempting to map and use it early on? We need more details to help further. > The kernel is configured very slim, could I be excluding necessary > functionality? Not really. Regards, -- Matt Porter MontaVista Software, Inc. mporter@mvista.com ** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/